TORONTO -- The effects of global warming have reached one of the coldest regions on Earth in southern Antarctica, according to U.S. researchers who discovered the remarkably preserved remains of an ancient penguin colony that was revealed by recent snow melt.
The penguin remains were found on the rocky and remote Cape Irizar, which overlooks the Ross Sea, in 2016 by a team of researchers from the University of North Carolina Wilmington led by Steven Emslie.
Emslie, who has been studying Adélie penguin migrations in Antarctica for the past 15 years, was working at an Italian research station in southern Antarctica when he made the discovery. He said he had heard there might be penguin guano (excrement) out at Cape Irizar, which puzzled him because there hadn’t been any record of breeding penguins in that area since its discovery in 1901.
“I thought this was really strange,” he told CTVNews.ca during a telephone interview on Thursday. “How could there have been a colony here that we missed?”
When he and his team reached the cape’s coast, they discovered pebble mounds that penguins use to build their nests in addition to plenty of guano.
The dry, rocky landscape was also littered with bones and carcasses from mostly chicks.
While some of the corpses were old and mummified, others appeared “fresh” with their bones and feathers intact that were only beginning to fall apart from decay.
“I’ve been on a lot of active colonies and at the end of the season, the penguins are gone, and there’s all these bones and things on the surface, guano, and it looked like that, like the penguins have just left,” he recalled.
Although he initially thought they had missed an active group of penguins there, it dawned on him that perhaps he had stumbled upon an ancient colony that had been buried by snow for centuries and it was only being exposed now due to a recent warming trend in Antarctica.
“Climate warming is starting to reveal things in the Ross Sea,” he said. “Before we hadn’t been finding that much there because it’s so cold in that part of the Antarctic that the warming trend hasn’t really affected it that much until recent decades and now it is.”
Like the famed discovery of Otzi the Iceman, the more than 5,000-year-old mummy of a human body, in the North Italian Alps in 1991, Emslie said thawing glaciers have been revealing archeological artifacts in the Northern Hemisphere for some time.
In the southern Antarctic, however, Emslie said has not been the case.
“This is the first time we’ve seen this in Antarctica and I think we’ll see more of it in the future with the melting trend,” he said.
DATING THE DISCOVERY
In order to confirm his suspicions about the origins of the remains, Emslie and his team excavated three of the pebble mounds and brought back samples of the bones, feathers, eggshells, and skin to his lab in North Carolina.
The remains were sent off for radiocarbon dating and the researchers studied historical satellite imagery for Cape Irizar to determine the timeline of the snow melt there.
Emslie said they discovered the remains they collected were from at least three separate periods when the penguins occupied the cape with the most recent being approximately 800 years ago and the oldest being 5,000 years ago.
The researcher said the penguins likely last occupied Cape Irizar during the “medieval warm period,” which began about 1,200 years ago and ended at the start of the “Little Ice Age,” approximately 800 years ago.
“I think that’s when the colony was being abandoned and then covered, still looking kind of fresh, covered and frozen for centuries, until it just recently re-emerged,” he said. “So that was the story.”
What’s more, the satellite imagery the researchers studied showed Cape Irizar gradually emerging from under the snow over the past decade, which is why they were able to discover the penguin remains.
Emslie said these findings are significant for two reasons.
Firstly, it proves that global warming has reached even one of the coldest areas of the planet and that snow melt is happening in southern Antarctica.
“Climate change is real, and it's happening there too,” he stressed.
Additionally, Emslie said their research, which was funded by the National Science Foundation and the U.S. Antarctic Program, tells them a lot about penguins’ responses to climate change in the past, which allows them to predict how they will react to future environmental changes.
“[This] in turn, helps for conserving areas where they’ll need, both the marine environment and terrestrial, and maintaining the species population through a conservation program,” he said.
The researchers' findings were recently published in the journal Geology.
